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Texas77Stepper 07-02-2010 10:33 AM

New 383 Build
 
This is my first post here.. looking for some good feedback hopefully.

Let me know what you guys think about this BUDGET engine build to go in front of a 700r4 with a 2500 stall converter. We are just about to put this guy together and drop it in a 77 step side.
  • Air Gap Vortec Intake Dual plane
  • Vortec Heads - 64 cc chambers/170 cc intake runner- 1.94/1.50 valves - .525 lift perf springs 110 # on the seat and 295 # open - Viton positive seals - 3 angle valve job
  • Clevitte rods and main bearings
  • 3.75 stroke crank 350 mains
  • block bored .030 over with torque plates for proper cylinder/ring seal
  • 383 stroker hypereutectic flat top pistons- right at 10.3 to 1 compression
  • Hi Volume oil pump
  • hardened steel shaft with pinned steel oil pump sleeve
  • Cloyes double roller timing chain
  • .488 / .488 lift cam with 234 degrees duration measured at .050(actual lift is .520 with 1.6 ratio roller rockers)
  • Pro full roller rocker arms self aligning for vortec heads
  • chrome molly pushrods - 4130 steel
  • crank rods and pistons spin balanced to plus or minus 1 gram
  • Pro Comp hydraulic flat tappet lifters
  • AC cam bearings
  • Pro Comp performance 65K volt distributor
  • Block clearance at oil pan rails and bottom of piston cylinder for stroker assembly
  • Cam degreed in straight up - no advance or retard
  • Holley 750cfm Double Pumper

If you think I should make any changes or missed something now is the time before we install. Remember this is a BUDGET build, cost is a factor. Thanks for any help.

Ticker 07-02-2010 11:29 AM

Re: New 383 Build
 
Looks great overall.

You don't want a high-volume or high-pressure oil pump - go with the Melling Select pump P/N 10553 and install the lower-pressure spring. The pump comes with a steel intermediate shaft, and requires a 5/8" pickup.

1.6 rockers with stock Vortecs often require drilling the pushrod hole out for clearance. Full roller rockers really aren't required for this build; a set of roller-tips is as far as I'd go - but it's your money :) Really, a set of the stock stamped-steel 1.5 ratio rockers would be fine (at $65 :)) and the heads won't flow past about .475 lift, so there's really no reason to lift it to .520. If you'll be turning this consistently past 5,500 RPM then let's have a different discussion. More info on the cam would be helpful, along with trans and gears.

Depending on what you're looking for the DP carb will only outperform a vacuum secondary carb 0-to-WOT, i.e. full-throttle standing starts. Otherwise is sacrifices fuel economy, driveability and low rpm throttle response.

Texas77Stepper 07-02-2010 11:50 AM

Re: New 383 Build
 
Thanks for the reply Ticker. I see you all over this site and your right on all the time. (Been lurking for a while now.) It's great to get your feedback.

This is going to be a daily driver with not much time over 5500 rpm. Looking for a lot of low end torque. The trans is a fresh rebuild that came with the truck. PO did some improvements, saying it should hold 450 hp. Still trying to get him to give more details... corvette servo... wide kevlar band... and...and... Also stock gears, not sure what we're running now.

Heads came from a friend complete as they are for $125. No brainer there for me. I've always had Edelbrock vacuum secondaries, so I thought it would just be something new to play, with having a DP.

What horse power do you think we can estimate from this motor?

Ticker 07-02-2010 12:48 PM

Re: New 383 Build
 
Thanks - I try to help where I can.

Knowing the RPM range of the vehicle is pretty important for cam selection - there's a big difference between 2.73 and 3.90 gears in terms of making the right power in the right RPM range.

Go ahead and try the DP if you've got the fundage - it is an interesting experience :)

Need more detail on the cam for an educated guess, but somewhere in the 400 HP/425 TQ range.

b&a72 07-02-2010 01:44 PM

Re: New 383 Build
 
Will a stock oil pump not work for a 383?

POPO1984 07-02-2010 01:58 PM

Re: New 383 Build
 
Sorry to Highjack. But I am building a 383 right now so we both might get some good info out of it.

Ticker said

You don't want a high-volume or high-pressure oil pump - go with the Melling Select pump P/N 10553 and install the lower-pressure spring. The pump comes with a steel intermediate shaft, and requires a 5/8" pickup

I have heard this before about the oil pump. what is the reason behind this.

What side of Houston are you on Texas77

Ticker 07-02-2010 02:02 PM

Re: New 383 Build
 
A stock-type oil pump is fine for a 383. What's happened in the last few years is that to reduce costs, the "over the counter" type pump castings have become thinner and thinner and cracks started being reported during high-performance use. It's smart now to invest in one of the Melling Select pumps which is a standard cast-iron pump, but just a heavier casting. They're still pretty cheap - around $85 for the pump and steel intermediate rod.

The NAPA MV-55 stock pumps now come with a little sheet of paper that states "NOT FOR HIGH-PERFORMANCE USE".

As for the high-volume, high-pressure stuff I'll stay off my soapbox and just note they are not only not needed, they actively suck horsepower and cause problems long-term.

Ticker 07-02-2010 02:05 PM

Re: New 383 Build
 
Quote:

Originally Posted by POPO1984 (Post 4070079)

I have heard this before about the oil pump. what is the reason behind this.

I direct you to a previous rant of mine on the subject ;)

http://67-72chevytrucks.com/vboard/s...0&postcount=10

POPO1984 07-02-2010 02:10 PM

Re: New 383 Build
 
Ok thanks Ticker.

b&a72 07-02-2010 03:48 PM

Re: New 383 Build
 
Your the man Ticker thanks!

Ticker 07-02-2010 04:24 PM

Re: New 383 Build
 
Most welcome, everyone. I hope it's all good information.

chris mc bride 07-03-2010 09:24 PM

Re: New 383 Build
 
Not to be a a$$ but I understand the reason for not going with high volume high pressure pump.I for one don't mind giving up a few hp for extra oil flow to my bearings.I run a very high pressure pump on my race engine.Many tell me the same thing.Sorry I fell to see where too much pressure and too much flow is bad,other than a few hp.If you can like the idea of less oil to your bearings under heavy load by all means go with standard volume pump.Then again what do I know only 20 years bulding pro drag race engines that make over 3000 hp.Yea I know these street motor are not on ragged edge like race engine,but then we are not talking pumps that make 120 plus pounds pressure.
If motor is basically stock low performance than standard pump is fine.If motor is stronger then IMO it need better lubrication.

cableguy0 07-03-2010 09:28 PM

Re: New 383 Build
 
The problem with high volume pumps on the street is that they suck the oil pan dry. You need to use a deep oil pan at least 6qt in the pan otherwise all that extra flow just goes dry at around 5500 to 6k rpm. Race engines and street engines are vastly different. There are almost zero similarities. Making it a 1/4 mile at a time and being freshened up every couple hundred passes is nowhere near the same as a street engine that will get nothing more than the oil changed every 3k miles if its lucky.

Ticker 07-03-2010 09:39 PM

Re: New 383 Build
 
Quote:

Originally Posted by chris mc bride (Post 4072140)
I for one don't mind giving up a few hp for extra oil flow to my bearings.

Sorry I fell to see where too much pressure and too much flow is bad

How does a high volume pump provides extra flow to the bearings? The bearing clearance is around .002...and only so much oil will flow through that space. Resistance to flow causes pressure, so we don't get more flow...we just get higher pressure...and so the pump goes into bypass.

Same thing with high pressure, the pump just goes into bypass.

If the pump is in bypass, it's not providing any additional lubrication. We're just losing horsepower.

This is pretty straightforward, supported by a ton of research and guideance from all the major engine builders.

Race engines aren't street engines.

We disagree, and that's cool . The OP and other readers can make their own decisions from what's presented :metal:

coater 07-04-2010 11:28 PM

Re: New 383 Build
 
I wish I seen this post before I ordered me pump. I'm building a sb 400 and just recieved my Melling HV oil pump.
Do I need to send it back for the other pump?

ripdog28 07-05-2010 01:19 AM

Re: New 383 Build
 
Great info so far. my only .02 input, with your projected 450hp, spend the extra $50-$100 on a set of Forged pistons.


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